This is from http://wyae.de/docs/img_dd.php. I wanted to copy it in case the site went away.

I have used this to P2V (Physical to Virtual) and V2P (Virtual to Physical) SuSE machines successfully and it worked great.

How to duplicate a complete PC via network

Imagine you get the task to quickly set up a number of identical workstations. Unfortunately either the available removable media (e.g. CD) is too small, or the imaging tool you use insists on not recognizing your favourite file system type (esp. Ext3, XFS, JFS, Reiser), or the duplication won’t work with your bizarre multiboot configuration. Here’s how to do with on-board tools.

Depending on the speed of your PC you should run no compression for low performance CPUs, compress for medium sized and gzip for CPUs > 2MHz.. Alternatively you could leave out the compression and store uncompressed images – if you have enough hard disk space and a fast network, that is. One problem is that GZIP won’t do more than 2GB image size, so beware… Requirements:

* Two or more identical PCs that are supported by the

* Boot media (floppy or CD) that can handle the hardware as well as the wanted filesystems, my recommendations: Knoppix CD in text mode ( http://www.knoppix.org/) and TRBT floppy ( http://www.toms.net/rb/). Make sure you’re logged in as ROOT user.

* Optonal an “image server” for central storage of the (different) image files – thus need for enough disk space.

* Network infrastructure for the PCs – a simple crosslink cable often is enough – is using an image server, a switched environment is preferrable.

* The netcat program – usually it is called “netcat”, but some other distributions call it “nc”

* If your harddisc is broken, use “dd_rescue” ( http://www.garloff.de/kurt/linux/ddrescue/ which will skip read errors. This way you can (try to) rescue data from a broken disc when simple TARing won’t do anymore.

Create the image:

* Install and configure the master PC (i.e. the PC to be imaged)

* Cleanup the disk space for each partition used for better compression, e.g. using:

dd if=/dev/zero of=empty.tmp bs=1024 count=FREEBYTESCOUNT

rm empty.tmp

* Start command on the image server to accept the image on an arbitrary TCP port (usually above 1024):

netcat-v -w 120 -p PORT -l < /dev/null > image.gz

* Within 120 seconds start sending the image from the master PC to the image server:

dd if=/dev/hda bs=512 | gzip -c | netcat-v -w 60 SERVERIP PORT

Flatten the “virgin” PC and impress the image:

* WARNING! This will utterly destroy each and all data on the PC involved!

* Boot with independent media and configure the network

* Prepare the image server to send the image:

cat image.gz | netcat-v -w 120 -p PORT -l

* Fetch image and impress it onto the PC’s harddrive:

netcat-v -w 60 SERVERIP PORT < /dev/null | gzip -dc | dd of=/dev/hda bs=512

* Reboot and accept the complaining FSCK which will run and correct without problems.

Copy PC On-the-Fly without using an image server

* WARNING! This will utterly destroy each and all data on the PC involved!

* Boot client with independent media and configure the network

* prepare the client to accept the image and write it directly to the disk:

netcat-v -w 120 -p PORT -l < /dev/null | gzip -dc | dd of=/dev/hda bs=512

* Send the image from the master:

dd if=/dev/hda bs=512 | gzip -c | netcat-v -w 60 SERVERIP PORT

* Reboot and accept the complaining FSCK which will run and correct without problems.